Electrical heating apparatus for the crucibles of linotype composing machines



Jan. 31, 1928. 1,657,581

o. MOZZALI ELECTRICAL HEATING APPARATUS FOR THE CRUCIBLES OF LINOTYPE COMPOSING MACHINES Filed Oct. 23, 1922 3 Sheets-Sheet l Jan. 31, 1928. 1,657,581

0. MOZZALI ELECTRICAL HEATING APPARATUS FOR THE GRUCIBLES OF LINOTYPE COMPOSING MACHINES .Filed Oct. 25, 1922 JSVSheetS- Sheet 2 attozneg Jan. 31, 1928. 1,657,581

- OZZALI O. M ELECTRICAL HEATING APPARATUS FOR THE CRUCIBLES OF LINOTYPE COMPOSING MACHINES Filed Oct. 23, 1922 S Sheets-Sheet 5 Patented Jan. 31, 1928.

UNITED STATES PATENT orrics.

ORESTE MOZZALI, OF TREVIGLIO, ITALY.

ELECTRICAL HEATING APPARATUS non 'rnn CRUCIBLES or LINOTYPE GOMPOSING MACHINES.

Implication filed October 23, 1922, Serial No. 596,346, and in Ita y November 3, 1921.

The object of the present invention is an electrical heating apparatus which is espe cially suitable for the crucibles of linotype composing machines.

The invention is illustrated in the attached drawings in which:

Fig. l is a side view of the resistance unit.

Fig. 2 is a plan view of Fig. 1.

Fig. 3 is a sect-ion on line 3-3 of Fig. 1.

Fig. i is a sectional view, on a larger scale, of the metal protective sheathing oi. the resistance unit. I Fig. 5 is a cross section of Fig. l.

Fig. 6 is an exterior view of Fig. 4:.

Fig. 7 is a plan view.

Fig. 8 is a section of the end box of the sheathing.

Fig. 9 shows the arrangement of the regulating rheostat.

Fig. 10 shows the rheostat seen from above.

Fig. 11 is a section of Fig. 15 on line 1717.

Fig. 12 is an elevation of the heater and the rheostat connected together.

The immersible apparatus for the melting of the metal consists of the following (Figs. 1 to 8) (a) The resistance unit, formed by a wire 1 of high electrical resistance and high working temperature (nickel-chrome alloy), is wound on mica plates, and insulated on both sides by other plates of the same material which are held in place by thin steel strips 2. The length and the section of the conductors are suitable for the tension and the strength of the current which must pass through the unit. The resistor is in the form of a semi-cylinder, having a lateral extension 3. along which the lead wires l and 5 01" the heating conductor are carried.

(6) The protective metal sheathing 6 of the resistor, consists of a semi-cylindrical covering of a non-oxidizable sheet steel, having the necessary lateral extension 7. The resistor is inserted therein and the edges of the latter are then sealed by means of electric welding, thus rendering it completely hermetic. .t is then placed under considerable pressure, so as to ensure the good adherence of its sides to those of the resistor. At the end of the extension of the sheathing there is a box 9, made from the same sheet steel in which two terminals 10 are fixed for connecting the ends of the heating conductor to two insulated copper wires 11 which teed current into the apparatus. An aluminum cover 12 and a flexible metal tube 13 protect the box and the copper wires.

The heat regulating rheostat for the crucible and outlet consists of the following:

(a) A resistor 27 comprises the heating wire, provided with three conductors 28, 29, and 30 which extend along the extension 31 ot the resistor together with the ends of the conductor itself. By means of this arrangement it is possible to vary the length of the heating conductor and consequently vary its electrical resistance by connecting it up through its two extremities (maximum r sistance), or with one extremity and one of the other three conductors, the latter being connected to the former at different points in its windings.

(b) A sheathing 32, which is hermetically welded together, surrounds the resistor.

(0) An aluminum box 38 which has a hermetically-closed cover, contains the terminals for connecting up five insulated copper conductors of the resistor.

The conductors outside of the box are protected by a flexible metal tube 38.

The size of the above-described regulating rheostat allows it to be placed inside the crucible heating apparatus and to be attached to it by means of two small bolts. By means of controller box handles, said rheostat can be placed in series with the crucible.

I claim as my invention 1. An electric heater for crucibles of linotype machines comprising a resistance unit in the form of a semi-cylinder; an extension for; said unit; a rheostat in the form of a semi-cylinder; and an extension for said rheostat, said resistance unit and rheostat being adapted to interfit and be secured together by means of said extensions to thus secure them to said crucible.

2. An electric heater for crucibles of linotype machines comprising a semi-cylindrical resistance unit provided with an extension; and a se1ni-cylindrical rheostat provided with an extension and adapted to fit co-axially inside of said resistance unit, said unit and rheostat being secured together to the crucible by means of the extensions.

3. An electric heater for crucibles of linotype machines comprising a semi-cylindrical resistance unit provided with an extension; 9. semi-cylindrical rheostat provided with an extension and adapted to fit co-axially with said resistance unit; and a terminal 100x secured to each extension, said unit and rheost-at being secured together and to the crucible by means of the extensions;

41 An electric heater for crucibles of linotype machines comprising a senincylindria October, 1922.

cal resistance unit; an extension on said unit; a protecting sheathing surroundlng 10 said unit and extension; a semi-cylindrical its extension; and means for co-axially securing the resistance unit and rheostat to gethenhy means of said extensions so that 1 said rheostat Will act as a heater.

Signed at Milan, Italy, this '6ti'1 dayof ORESTE MOZZALI. 

